Grinder



Sept. 28 1926. 1,601,227

H. D. STEVENS GRINDER Filed Ferb. 26, 1924 4 Sheets-Sheet l Sept. 28 1926. 1,601,227

H. D. STEVENS GRI NDER Filed F'eb. 26, 1924 4 Sheets-Sheet 2 sept. 28,1926. Y1,601,227

H. D. STEVENS A GRINDER -Filed Feb. 26, 1924 4 Sheets-Sheet 4 753 Mms atented Sept. Z, 1926.

FFEQ.

HORCE D. STEVENS, OF AKRON, OHIO, .ASSIGNOR- TO THE FIRESTONE TIRE AND RUB- BER COMPANY, 0F AKRON, OHIO, A CORPORATION OF OHIO.

GRINDER.

Application filed February 26, 1924. Serial No. 695,206.

. rIhis invention relates kto grinding machines and especially to a machine for grindingl to shape the opposite ends of articles such as rubber pedal pieces.

The chief objects of the invention are to provide means whereby more accurate work may be accomplished in much less time with little labor and at low cost. More particularly, the purposes of theinvention are to provide largely automatic means for applying worl to grinding rolls, automatic means for rotating the work relative to the rolls as the work-applying means is advanced into cooperative relation with the grinder rolls, and means whereby a plurality of work-applying means may be so advanced into or withdrawn from cooperative relation with the grinder that while an article, supported in one work-applying means, is being ground, a finished article can be removed from another work-applying means and an article-blank to be ground inserted therein in readiness for a grinding operation.

Morespecific objects are to provide a pair of work-applying means so connected that as one is swung into cooperative relation with the grinders, the other is swung out of such cooperation, to provide yielding means for swinging the work-applying means so that the work will be maintained against the grinders as the grinding proceeds, means being provided to limit 'the motion of the work-applying means so that the depth of the grinding may be predetermined, and to provide yieldably mounted means for engaging the work-applying means and rotating the work therein as the worlapplying means is swung into cooperative relation with the tool.

Another obj ect is to provide means for automatically positioning the work relatively to the grinder as the work-applying means is advanced intocooperative relation therewith.

Other objects will appear from the followj it being understood that I do not limit my invention to the specific embodiment thereof shown in the drawings. 5

Of the accompanying drawings: Figure 1 is a front elevation of a machine embodying my invention and adapted for grinding rubber pedal pieces; Y

Figure 2 is a right eleva-tion of the machine as shown in Figure 1; Y

Figure 3 is asection on line 3 3 of Figure 2;

Figure 4 is an enlarged section on line 4 4 of Figure 1;

Figure 5 is a detail section on line 5 5 of Figure 2; p y

Figure 6 is an enlarged section online 6 6 of Figure 1; and

Figure 7 is an eleva-tion of a rubber pedal piece, the ends of which have been ground to shape in the machine.

While I havel shown in the drawings: a machine primarily adapted to sha-pe the ends of rubber pedal pieces, it will be understood that my invention is capable of general application to machines for forming various articles of meta-l, fibre, rubber, etc.

In the drawings, 1 designates a table or bench having an opening 2 in the top thereof, over which is mounted a base plate 3 having an opening 3a therein, the plate 3 substantially covering the opening 2. Mounted on the plate 3, respectively forwardly and rearwardly of the opening 3a, Vare bearing brackets 4 and 5, and secured to the under side of the plate 3, forwardly and rearwardly of the opening 3a, and projecting downwardly through the opening 2 in the table 1 are the bearing brackets 6 and 7.

Respectively mounted on brackets 4 and 5 are brackets 8 and 9 adapted respectively to form, with brackets 4 and 5, separable bearings 10 and 11 in which is journaled a grinder drive shaft 12 having secured thereon a pulley 13 for driving the shaft 12, the pulley 13 being driven by a belt 14 trained over a pulley 15 on the shaft kof a motor 16.

For mountingthe shaft 12 in the bearings 10 and 11, sleeves 14, 14 (see Figure 4) are secured thereon by set screws 15` 15. Each sleeve 14 is threaded at either side of each bearing 10 or 11 and the shaft is longitudinally secured in the bearings by washers 16, 16, nuts 17, 17 and lock nuts 1S, 18.

For adjustably mounting grinder or emery wheels 20, 2O tooperate upon articles of different sizes, sleeves 14 preferably are formed of such length as to extend inwardly from the bearings 10 or 11 toward the center ot the shaft. rEhe emery wheels 2O are secured on the sleeves M by discs 2l, 2l screwthreadedly mounted on the sleeves l and by nuts 22, and lock nuts Q3 engaged on the sleeves 111-, washers Q-L, 2l being interposed between the nuts and the emery wheels Q0. rlhe emery wheels 2t) may be for ned integrally in the shape shown in the drawings7 but preferably are formed ot two discs 20 and Q0", each ot which is adapted to he removed and replaced by a dise ot different shape.

F or advancing` the work toward and 'troni the emery wheels 20, there is provided work carrying` arms 25, secured on a rock shatt 26 journaled in hearings and termed respectively in racket S and l rL eket 9. Since the work is to he "ieldingly held against the einery wheels 20 to maintain it against the wheels as the erinding proceeds, provide lluid pressure cans tor rockinf the shatt Q6. rEhe fluid essure means inclu les a double-acting` pis mounted in a. cylinder Si) i on bracket 9, the upper il ton slidably hic i mounted ti in ot the cylinder being; slotted nd the p sten jacent the slot in the cylinder beine toriued vith rack teeth 31 (see Vfigure E). wheret a sector gear 3:2 secured on the shalt QG permitted to Xtend into the cylinder 30 and into engagement with the rack teeth 3l. For admitting` fluid pressure lirst to one side and then to the other ol the piston 9.9. a pipe 33 is connected to the cylinder 3() at jacent one end and a pipe 33 is connected to the cylinder SO adjacentthe other end, the pipes 33 and being,l connected to a suitable Yalve 3ft to which is connected a fluid pressure supply pipe 35. 5i hand lever is provided tor operating` the valve. It is desira'ble to damp the motion in'iparted to the work carrying arms by the Huid pressure and to this end there is provided a dash pot 3T pivotally mounted on the base plate 3, the piston ot' which dash pot is connected by z rod 3S to an arm 39 secured on the shaft Q6. For limiting the motion ot' the rock shaft 26, an arm lO is secured thereon and projects between two lugs all, all secured on the bracket 8E bolts Ll2, l2 bciircl `.idjustal ly secured to the lugs tor engaging the arm y() to limit its swing.

in the production ot rubber pedal pieces it is necessary that the work be rotated as it is beingv ground.. For this purpose the end ot' each arm is formed with c separable bearing` adapted removably to receive a rotary work carrying` member #t3 which, in this instance, is formed vitli a square vork receiving aperture s adapted to receive a pedal piece, designated f 3, wliie is square in cross-section. Each work carrying member may be driven by a gear t6 tor ned thereon.

Means are provided which are adapted to drive fl-G as the work carry-'npr aims are advanced into cooperation with the eniery wheels. These means comprise arms at?, t7 journaled on a rod t secured. :is indicated at t8 and l-5b respectively, in brackets fl and Each arm ,ltormc l with a projection extending between apert ed lugs 50, 50 formed on the base plate 23. ,i spring 5l is secured to a plug f" mounted in one lug ft). the spring 5l he j scured to the 'ejection Lll) and` oruially tending to urge e rm il upv-ra ly. and a holt :37E is adjustably secured i l't to limit n the othell th upward notion oi the arm A gear is so journ: `ed on the end each arm at aptt d i d? as te be d csh with a gear if) on a work carrv if; arm. For driving` each fear a sproc..et is secured thereto and a sprocket chain ft' is trained over the sprocket (ll 'ed on a shaft (l2 journaled in the bracket. and T. 'l'he .shaft (33 may he driven hv a pulley (113 secured thereon.

The gears are to he driven slowly as eompared with the em wheels and. ac cording'ly, puilcy {Si} is driven by the same,

source ot pov-:er the emerj.Y wheels.y c.. by motor lf3. suitable speed reducing` "ansmission is required. TEoithis reason a helt (il is trained over pulley (lf3 and over a small pulley G5 rohtably niotuited wi h a large pulley GG in brackets, indicated at (3T. .secured on the table l, and a belt (3d trained over the large pulley (3(3 and over a small pulley GS) secured on the shatt ot the motor 1G.

For withdrawingr the grinder dust from the machine and conducting; it 'i'rom the room in which the machine is installed. a casing TO so mounted on the machine as to enclose the `grinder smc-elf. a opening` Tl being` provided in the casina' to permit the entrance and exit ot the work carrying a `ms and a .second opening being` provided to clear l and to the parts if permit the passage ol drive chain (it) therethrough. A duct il leads t'roni the easing 'TO to a suitable suction tan (not shown).

It is frequently essential. as when articles are being `ground to a delinite length between spaced grinder wheclr 20, that the articles be properly positioneoA in the work carrying arms so as to he carried in propeposition to the wheels 20:1. ln cert; in instances this may be etlected by positively clampingr each article in position in the arms "3. For the production oi'f article-z` such as the pedal pieces 5, however, l provide automatic means for positioning articles supported in arms as the latter are .swung into cooperative relation with the grinders. The article positioning means comprises angle pieces or guides 74, 7 4, one on the casing 70 at each side of the opening 7l in line with the movement of each work supporting, apertured member 43 toward the emery wheels 20.

Each guide 74 is formedwith a slotted arm 74 are adjusted to permit an article blank to pass therebetween and to guide the same in proper relation to ,theemery wheels. Bolts 42 are also adjusted to limit the swing of the arms 25 so as toA gage the depth of the grinding, and bolts 53 are adjusted so as .to permit the arms 4? to be urged by springs 5l vinto such position as to mesh with gears 46 at the limit of swing of arms 25. Power is. then supplied to the motor 16 whereby the emery wheels 20 are rapidly ro tated and gears 54 are slowly rotated each in the sameV direction as the emery wheels Assuming that the parts are in the position shown in Figurel, an article-blank is ini serted by the operator into the aperture 44 and the lever 36 is swung clockwise, thus admitting air pressure through the pipe 33a into the right end of cylinder and forcing piston 29 to the left whereby rock shaft 26 will be rocked clockwise, thus swinging the 4right work carrying arm 25 toward the emery wheels 2O and simultaneously swinging the left work 'carrying arm 25 away lfrom the emery wheels. As the work is carried between the guides 7 4, if it be not already in proper position in the aperture 44, one or the other of the guides will Contact with the end thereof and shift it into proper' position so that it will be centered with relation to the emery wheels 20.

As the right work carrying arm 25 approaches a position in cooperative relation with the emery wheels 20, the gear 46 thereon automatically meshes with the right drive gear 54 and drives the work in a direction opposite. to that of the emery wheels 20, the gear 54 receding slightly from the position in which it is mounted by the action of arm 47 urging projection 49 against spring 5l as the meshing is effected, the gears 46 and 54 being retained in mesh as the grinding proceeds by the yielding pressure of the spring. f

Presently the work contacts with the emery wheels 20 and is maintained in such contact as the grinding proceeds by the fluid pressure constantly being exerted on the piston 29. The depth of t-he grinding is determined by the position of bolt 42 which engages arm and prevents further rocking of the shaft 26.

.While the grinding operation is being per` formed, the operator removes a previously ground article from the left work carrying arm 25 and inserts an article blank into its aperture 44, as described above. At the completion-of the grinding operation, the lever 36 is swung back to the position shown in yFigure l, thus carrying the article blankl in the left arm 25 into'cooperation with the emery wheels 20 and carrying the finished work in right arm 25 out of such cooperation, as will be understood.

Modiiications may be resorted to without departing from the spirit or scope of the invention as claimed in the appended claims.

l. A tool, a plurality of work carrying means relatively movable toward and from said tool, yielding means for simultaneously urging one work carrying means relatively C toward-said tool and urging Vanother work carrying means relatively away from said tool, and means for limiting the relative motion toward said tool of each of said Work carrying means. l

2. A tool, work carrying arms osoillatable toward and from opposite sides of said tool, a rock shaft on which said arms are secured, and means operable to rock said shaft simultaneously to swing one arm toward said ltool and to swing another arm away from said tool. i

3. A tool, work carrying arms oscillatable towardand from opposite sides of said tool, a roc-k shaft on which said arms are secured, a gear secured on said shaft, a reciprocable rack meshed with said gear, and Huid pressure means for reciprocating said rack.

4. A tool, a work carrying arm oscillatable toward and from said tool, a rock shaft to which said arm is secured, a gear on said shaft, a slidable rack meshing with said gear, and fluid pressure means for sliding said rack.

5. A tool, work carrying means relatively movable toward and from said tool, a rotary work supporting member mounted on said means, a gear on said member, a gear yieldingly mounted adjacent said tool, and means for driving said last mentioned gear, said gears being adapted to mesh as the work carrying means is moved into cooperative relation with said tool.

6. A tool, a rotary work supporting member movable toward and from said tool, means on said member for rotating the. same, means for driving said last mentioned means as said member is moved into cooperative relation with said tool, said driving means being mounted on an arm, and means for yieldingly urging said arm to maintain Said driving means in engagement with the Work rotating means as the tool cuts into the Work.

T. A tool, a rotary Work supporting member movable toward and from said tool, a gear on said member for rotating the same. a drive gear mounted adjacent said tool, a pivoted arm on which said drive gear is mounted, a sprocket secured to said drive gear, a second sprocket mounted on the pivot of said arm, a chain trained over said sprockets, means for driving said second sprocket, and means permitting said arm to yield as the gear on said Werl; supporting member is moved into mesh with said drive gear. l

S. A tool7 a Work carrying member for loosely receiving the yvorl: and movable toivard and from said tool, and means adjacent the path of movement ot' said member 'lor engaging and positioning the Work therein as said member is advanced toward said tool. 9. A .tool comprising spaced elements i'or operating upon spaced .portions of an object, means movable toward and rom said tool for carrying said object into contact therewith, and means disposed adjacent the path ot' said last mentioned means for vso aperture.

1l. A tool, means movable tonard and from said tool for applying an object to the tool, said means having an object-receiving aperture, and adjustable means at either side ot the path oll said Work applying means tor shitting the object into proper position in A said aperture.

l2. )i grinder comprising spaced abrasive Wheels relatively adjustable on a shaft` a vforl; carrying device movable toward and 'from said spaced Wheels, and means adjacent y either side o'l' the path ol said device lor positioning work in said device, said means being relatively adjustable so that they may vLe secured in alignment with the spaced Wheels.

HORACE D. STEVENS. 

